I'm planning on replicating a project I've seen online once I get the parts. I'm planning on using Nanos. The project consists of two modules. For each module there are multiple components, some specifically require 5V. I've noticed that the Nano has fewer 5V pins than the Uno. I would like to know if you can attached more than one component to a 5V pin or if there some other way of getting around this issue.
The person who originally created the project used a Nano and a Uno. However, they mentioned in there document that two Nano's can used instead.
Here is brief list of components that require 5V according to the schematics (Which I've also included).
Nano Module One
1.3 OLED
NRF24L01+
LM386 AMP
3 X Push Buttons
Number of 5v pins on the MCU is not important. You won't power the modules through the 5v pin on either module. Instead, you run power to the 5v pin on the MCU and the 5v pins on the modules, all from the 5v source, such as a wall adapter.
What is the battery. Be careful when using the power plug or Vin. Powering through Vin or the power jack means that the Arduino and all peripherals that are on the 5V rail are powered by the onboard 5V regulator. The on board 5V regulator is not heat sinked so will supply limited current before it overheats and shuts down. The amount of current depends on the voltage input to Vin or the power jack. The higher the voltage the less current can by supplied. I would use a buck converter to drop the higher voltage to 5V and connect that to the 5V on the Arduino, bypassing the, weak, 5V regulator. Then the rated current of the DC DC converter is available on the 5V line.
Where do you find NRF24L01 modules that are powered by 5V. All that I have seen are 3.3V powered and will be damaged by 5V to their Vcc. The 3.3V regulator on a Nano will not provide the necessary current for a NRF24L01. There are adapters available that take 5V and output 3.3V and the current required by the radio modules.
So you are completely unfamiliar with working with electricity, eh?
I am puzzled as to why your "Finish Module" has a LED powered by the 3.3 V pin. Perhaps this is the same question.
It is a conceptual problem. In an electronic circuit, you may connect many things together to the one point, particularly to the power and ground supply terminals. It is just the same as in your house - power cables run in the walls from one power outlet to the next so that many connect to the same circuit breaker in the supply box. In case it is not clear, there are connectors specifically designed to facilitate this, screw terminals on the rear of power outlets enabling two or even three wires to connect to the one terminal.
It is misleading to think that the "Dupont" jumpers used with Arduino (or similar) kits are a common way of connecting electronic circuits. They are entirely an oddity made for the purpose of experimentation, assembling temporary circuits. Actual electronic systems are connected by Printed Circuit Boards - like the Arduino module itself - with wires soldered to pads on the boards or to pins. Either the PCB arrangement or the pins facilitate connecting a number of wires to a given terminal point.
You will notice the the "solderless breadboards" available have strips of sockets allowing either five wires to connect together, or longer socket strips along the edges to allow many more to connect. If you only wish to make temporary experimental circuits, these are very practical - especially for Nanos with their pin headers soldered - otherwise you need to equip yourself for and learn to solder.
